Prior Art oil coolers are generally formed with a body portion having inlet and outlet means and a plurality of cooling elements operatively connected to said inlet and outlet means. The fluid to be cooled (generally oil) enters the inlet means, passes through the cooling elements and exits through the outlet means. The cooling is a continuous process. The pressure of the fluid is produced by pressure means such as an oil pump.
In order to increase the surface area of the fluid to be cooled the cooling elements are provided with baffles to induce turbulence within the fluid as the fluid passes through the cooling elements. These baffles, at the same time, increase the surface area of the fluid so as to enhance the rate of heat transfer from the fluid to be cooled to the cooling elements.
In the prior art structures, however, the baffle members are circular in cross section because of the ease of construction and the concomitant reduction in tooling costs. Baffles of non-circular cross section are more costly to produce than baffles of circular cross-section.
The present invention solves the problems involved by providing baffle members of substantially polygonal cross-section which, in turn, provides more efficient cooling and, at the same time, reduces the additional cost of the manufacture of such baffles by providing fewer cooling elements which thus require less material. Furthermore the polygonal baffle members of this invention also aid in allowing the flow of the fluid to be cooled when passing through the cooling elements to cause additional three dimensional turbulence while, at the same time, reinforcing the structure of the cooling elements to withstand the pressure exerted by the fluid passing through the channel within the cooling elements. Thus the cooling elements can be made light enough to provide adequate cooling but strong enough to support the pressure that they are subjected to. With the polygonal shape of the baffle members the surface area available for cooling the fluid involved is also increased therefore enabling a higher rate of heat exchange from the hot fluid to the cooling elements while the added turbulence and time for the portion of the hot fluid that is in direct contact with the cooling elements further enhances the rate of heat transfer. Thus the cooling device of this invention is more efficient than conventional cooling devices and is less costly to manufacture.
In the preferred embodiment of this invention the baffle members are offset from one another so as to increase the turbulence of the fluid to be cooled as it passes through the respective cooling element. The invention also includes novel constructional features which improve the device and make it easier to manufacture.
The fluid cooling device of this invention is provided with oppositely disposed inlet and outlet channels each closed at one end thereof. A plurality of spaced cooling elements extend longitudinally between said inlet and outlet channels, with each of the cooling elements provided with a channel therethrough which is open at both ends thereof, one end of the channel in each cooling element communicates with the inlet channel and the opposite end of the channel within each of the cooling elements communicates with the outlet channel. A plurality of baffle members are disposed within the channel within each of the cooling elements and are adapted to cause turbulence within the said cooling element when a fluid under pressure passes therethrough. Each of the baffle members are substantially polygonal in cross-section and extend transversely across the channel within the respective cooling element so as to also provide support and prevent rupturing of said cooling element due to the pressure of the fluid passing therethrough.
In the preferred modification of this invention the baffle members are rectangular in shape having rounded corner portions and the cooling elements consist of a plurality of spaced series of longitudinal plates. Each member of each series of plates is formed with a pair of such plates disposed one above the other with the space between the said pair of plates defining a channel therethrough. The inlet and outlet channels are also defined by the structure of the aforesaid plates. The baffle members are integral with the plates involved.
The upstanding portions of the baffle members of one of the plates composing one member of each of such series of plates is in abutting relationship with the upstanding portion of the baffle members of the other plate of such series of plates.
The baffle members are adapted to cause turbulence within the third channels when a fluid under pressure passes therethrough. Each of the baffle members is substantially polygonal in cross-section and extend across said third channel. The baffle members also provide support and prevent rupturing of each of the plates due to the pressure of the fluid passing therethrough.